The proline-rich region of TSAd is important for CXCL12 induced actin polymerization and migration.

<p>(A) Jurkat T cells transiently transfected with plasmids encoding GFP (−), or GFP fused to wild type TSAd or TSAd Δ239–274 were left unstimulated (-CXCL12) or stimulated with 100 ng/ml CXCL12 for 15 seconds prior to staining of F actin with Alexa 546-phalloidin followed by flow cytometry analysis. The F-actin content was assigned as mean fluorescence intensity value of FITC-phalloidin stained cells. Data shown are F-actin content relative to F actin in unstimulated cells expressing GFP. Mean values +/− standard error of the mean (SEM) from four independent experiments are shown. (B) Jurkat T cells were transfected as in A with plasmids encoding GFP and TSAd, either in fusion or as separate proteins, and assayed for migration towards 100 ng/ml CXCL12. Migration index was calculated as the number of GFP-positive cells migrating in response to CXCL12 divided by GFP-positive cells migrating towards medium only. The mean migration indices of four independent experiments with SEM are shown.